x86-64: correct read/write barriers

Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/arch/arch-x86_64.h b/arch/arch-x86_64.h
index 665c6b0457befa70c2091902665bafd1b184316e..0cd21b8f039925bde00261d41650a74ba18844b0 100644 (file)
--- a/arch/arch-x86_64.h
+++ b/arch/arch-x86_64.h
@@ -27,8 +27,8 @@ static inline void do_cpuid(unsigned int *eax, unsigned int *ebx,
 #define        FIO_HUGE_PAGE           2097152
 
 #define nop            __asm__ __volatile__("rep;nop": : :"memory")
-#define read_barrier() __asm__ __volatile__("lfence":::"memory")
-#define write_barrier()        __asm__ __volatile__("sfence":::"memory")
+#define read_barrier() __asm__ __volatile__("":::"memory")
+#define write_barrier()        __asm__ __volatile__("":::"memory")
 
 static inline unsigned long arch_ffz(unsigned long bitmask)
 {